The R/T uses a composite intake manifold. For better throttle response, ground the TB to the engine block. A couple of other tips when using a drive by wire TB in bracket racing is to disconnect the battery between rounds so the factory PCM adaptives don't have a chance to take over and you'll run more consistant. I've also tried shutting the engine off and restarting it after my burnout which then puts the PCM back into closed loop startup for about 20 seconds or so. Going for fast times I leave the line from an idle. My short times have always been faster this way vs loading the converter, but my reaction times ain't pretty lol. When I leave off the converter my reaction times are always the best and I run way more consistant and brought me home some paycheck's.